1. Field of the Invention
This invention relates in general to devices for igniting a gas, and in particular to an igniter having an electrical sparking device for creating a flame, which is discharged across a flare pipe or stack to ignite the waste gas being discharged from the pipe or stack.
2. Description of the Prior Art
An igniter of the type concerned herein is a device that is mounted near the discharge end of a vertical or horizontal flare pipe or stack. The igniter has a tubular housing with a gas line running through it which terminates in a nozzle. An electrical spark means is located near the nozzle. A source of gas is supplied to the fuel line, which is ignited by the igniter, to direct a flame across the open end of the discharge pipe. The flame ignites the gas being discharged.
Often, the gas being discharged is of low pressure and intermittent in its flow rate. Wind or an interruption of supply, may cause the combustion of the flare gas to cease. Because of the possibilities, it is important that the igniter have a flame continuously present. However, the supply to the igniter may be intermittent as well. On very high stacks, it is hard to see whether or not the igniter flame is ignited, particularly during daytime. One method used to remedy the possibility of the igniter flame going out is to periodically pulse the electrical spark. However, again, one can not be sure in some cases whether or not the flame is reignited, due to the possibility of poor gas being supplied to the igniter or a malfunction in the igniter.
Another disadvantage of prior igniters is in servicing the igniter. Unbolting the igniter from the stack can be dangerous and time consuming. Removing the inner components from the igniter housing often requires climbing to the top of the housing to loosen bolts and the like.
Another problem encountered in burning waste gas in some types of plants is the need for burning leakage gas. Leakage gas is usually made up of small amounts of gas from various points within a plant, which in themselves may be too small in volume to be conventionally discharged from a stack with larger flow rates. This normally requires a separate low volume stack.
Other improvements in the burning of waste gas are also desirable, including improving the igniter nozzle to further reduce the chance for wind or rain to extinguish the flame.